Retraction Sought in Study on Views of Gay Marriage

The senior author of a widely covered study suggesting that gay political canvassers could change conservative voters’ views on same-sex marriage has asked that the report be retracted because his fellow author failed to produce the raw data. The study appeared in December in the journal Science, and numerous media outlets, including The New York Times, published articles on the findings.

Marcia McNutt, editor in chief of Science, said in a statement that “Science takes this case extremely seriously and will strive to correct the scientific literature as quickly as possible.”

Dr. McNutt’s statement said that the study’s senior author, Donald Green, a prominent political scientist at Columbia University, had submitted a request for a retraction on Tuesday after his co-author, Michael LaCour, a graduate student, “admitted that some of the details of the data collection were falsely described in the published report.”

The statement continued: “At this time, our editorial staff is assessing the report. Given the fact that the Dr. Green has requested retraction, Science will move swiftly and take any necessary action at the earliest opportunity.”

On Wednesday, the journal published an “editorial expression of concern” to inform readers that “serious questions have been raised about the validity of findings” in the study.

The questions began when two graduate political science students at the University of California, Berkeley, tried to do what they called an extension of the study, but found problems in the data. The students, David Broockman, who will soon be an assistant professor at Stanford, and Joshua Kalla, noticed that the response rate of their pilot study “was notably lower” than what the original study reported, according to a timeline they posted on Tuesday. They then contacted the research firm said to have conducted the canvassing groundwork on which the original Science report was based. Prof. Peter Aronow of Yale was a co-author of the timeline.

“The survey firm claimed they had no familiarity with the project and that they had never had an employee with the name of the staffer we were asking for,” Dr. Broockman and Mr. Kalla said in their post. “The firm also denied having the capabilities to perform many aspects” of the original study.

The study’s senior author, Dr. Green, then made his own inquiries and found that the study’s first author, Mr. LaCour, “declined to furnish” the contact information of people purported to have taken part in the study, according to a letter published along with the timeline.

Reached by phone Wednesday evening, Mr. LaCour said, “I am under legal advice to not speak,” adding that “I am gathering the evidence and relevant information needed so that I can make a comprehensive response.”

Mr. LaCour said the researchers criticizing his work did not contact him before posting their report. “I didn’t have a chance to read it and formulate a response,” he said.

Asked how he was feeling about the situation, Mr. LaCour said, “I’ll be fine.”

The study was intended to test the effectiveness of a door-to-door campaign run by the Los Angeles LGBT Center after the passage of Proposition 8, which banned same-sex marriage in California. Dave Fleischer, director of the center’s leadership lab, said he wanted the study to assess the center’s effectiveness in using 20-minute conversations to try to change opponents’ minds.

He said Mr. LaCour’s role was recruiting voters in precincts that strongly supported Proposition 8, randomly assigning them to receive a placebo (no canvassing or a conversation about recycling) or “treatment” (one of two scripted conversations involving same-sex marriage). Mr. LaCour was to enlist a survey firm to question voters online before canvassing and several times afterward.

The results suggested that gay canvassers, but not straight ones, could induce lasting attitude change favoring same-sex unions. More broadly, the findings implied that people with personal stakes in controversial issues, could change voters’ minds with face-to-face conversations.

Mr. Fleischer said he believes Professor Broockman and Mr. Kalla, who are studying the center’s canvassing to increase support for transgender issues in Florida, will produce a solid evaluation of the approach. Regarding same-sex marriage, though, “there is no time machine to take us back,” Mr. Fleischer said.

“How it feels is like a punch in the gut,” he said. “It really hurts when you trust somebody to be doing an honest assessment of your work and then it turns out that they did not. We have a wealth of qualitative data that has made us feel like we’re having an impact, but we are well aware that that’s not a substitute for independent information.”

Correction:

Because of an editing error, an article on Thursday about a political scientist who is seeking a retraction of a study published in the journal Science, which suggested that gay political canvassers could change conservative voters’ views on same-sex marriage, erroneously included one news organization among those that had issued editors’ notes regarding their initial coverage of the study. NPR did not report on the study and has not posted such a note; the radio program “This American Life,” which is produced by Chicago Public Media and delivered to stations by PRX The Public Radio Exchange, did post a note.

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